1. Field of the Invention
The present invention relates to an image display control device for video data which can be viewed on a TV receiver, wherein the image display control device prevents or permits viewing of video scenes included in the video data in accordance with contents thereof.
2. Description of the Related Art
Data broadcast to TV receivers may have a good or bad influence on the development of children who view that data. Recently in the US, in consideration of the healthy growth and education of children, legislation has been introduced to make compulsory the provision of a function for automatically preventing the viewing of video scenes regarded as inappropriate for the growth and education of children (for instance, video scenes of extreme violence, sexual nature, or the like) for the period of their broadcast during certain programs broadcast on TV receivers with screen-width of 13-inches or above.
The XDS (eXtended Data Service) is provided in North America and Canada The XDS now offers the information included program information (i.e. station ID and Network and Program Name), time information, a weather forecast, and so on. XDS data is multiplexed on the 21st horizontal tracking period of the vertical retrace of a video signal transmitted from a TV broadcasting station or a video signal played-back on a VCR or the like, and has same structure with the caption standard on the XDS.
More specifically, the above-mentioned function is realised by using 1 XDS data (program rating) for text display and the like which is multiplexed on the video signal.
When preventing viewing of video scenes regarded as inappropriate for moral (i.e. the growth and education of children) while viewing a certain program on a TV receiver, the broadcasting station sends numerous types of restrict data which are multiplexed onto the 21H of the vertical retrace period so that viewing can be permitted or prevented in accordance with the level of appropriateness. The restrict data is extracted from the video signal and decoded, and viewing of the TV image is prevented (for instance, the whole screen displays a predetermined color) in accordance with the decoded result.
However, the restrict level determined by the broadcasting station is not necessarily the same as the restrict level desired by viewers who view the broadcast pictures on TV receivers. In other words, there are cases where the broadcasting station wishes to restrict viewing but a viewer does not, or vice versa. However, with conventional technology, image display is restricted only according to a restrict level set by the broadcasting station, and the wishes of the viewer are not reflected.